Management of mallet finger is both difficult and controversial. Sequelae are not uncommon, particularly after surgical treatment. Many authors advocate orthopedic treatment, which is less invasive but requires greater patient participation to implement. Despite the large number of orthopedic methods proposed, none has proven superiority. We report here our experience with a dorsal adhesive splint, which preserves digital pulp function and improves patient compliance.

This retrospective analysis included 270 mallet fingers presenting 153 tendon injuries and 117 bony injuries in 265 patients aged a mean 42 years and treated from 2003 to 2005. Most of the tendon injuries involved the medius (38.7%) and most of the bone injuries involved the ring finger (35.4%).

A splint was fashioned for the two distal phalanges and glued to the nail plate filed for this purpose. The splint was fashioned out of an L-shaped plastic sheet of thermomoldable plastic dipped in hot water (60°C). The L was molded to the dorsal aspect of the phalanges and rolled like a ring around the second phalanx, then glued to the nail. The splint was worn for 8 weeks by patients with a tendon injury and 6 weeks for those with a bone injury. The splint was then worn at night for 2 weeks. Three criteria were used to analyze outcome: residual extension deficit, joint involvement, and complications.

Mean follow-up was 18 months. Mean time from injury to definitive installation of the splint was 6 days. The complication rate for this orthopedic method was 14.3%, with complications observed in 6% of patients. All complications were transient except for one case of swan neck deformity and one case of painful osteoarthritis. Thirty splints (11%) became unglued but were all reinstalled using the same protocol.

Thirty fingers (14%) presented residual deficit of active extension measuring less than 20°. The quality of the result depended on the type of injury: tendon injuries led to extension deficit in more fingers (20% versus 7.5%) but to a lesser degree (16.5° versus 19.1°) than bone injuries.

We observed a lower rate of complications with this technique than usually reported in the literature. Transient nail dystrophy involved only 2.5% of the fingers in our series. Swan neck deformity was observed in only 8.3% of the fingers, all with tendon injuries, and resolved in all. There was only one case of symptomatic distal interphalangeal joint degeneration among the 117 fingers with bone injuries. There were no cases of skin necrosis.

The results of this retrospective study, with a mean 2.38° extension deficit, are better than reported in other series in the literature. These results suggest that surgical indications for mallet finger should be revisited, irrespective of the type of injury, except when subluxation persists despite installation of the splint.

In conclusion, our series demonstrates that the adhesive dorsal splint is an effective treatment for all types of mallet finger, reducing the number of indications for surgery. Compared with other techniques, the advantages are free digital pulp, better patient compliance, and less extension deficit.